The vast majority of cases of Pancoast syndrome are due to lung cancer. Rarely, other lesions arising in the superior sulcus can cause Pancoast syndrome. This case emphasizes the importance of securing a histologic diagnosis before proceeding with treatment. The effect of radiotherapy on the underlying lesion is discussed.
A 49 year old man presented with 3 weeks of severe left sided chest pain, and minor hemoptysis. He had lost 40 lbs over the preceding year, and complained of severe anorexia and fatigue. He denied any fever; there was no history of tuberculosis. He lived in Canada since 1987, after having left Romania. He was a longstanding heavy smoker. The physical examination revealed a cachectic man, who had finger clubbing. There was no lymphadenopathy, and the neurological exam was unremarkable. The CXR revealed a left upper lobe (LUL) mass. On CT scan, a large irregular mass in the LUL with destruction of the second and third ribs was noted, as well as severe emphysema. No endobronchial lesion was seen on bronchoscopy. The BAL cytology revealed atypical cells, suggestive of malignancy but insufficient to establish a diagnosis. No acid-fast bacilli (AFB) were seen and mycobacterial culture was negative. Based on the above findings, the diagnosis of lung cancer was accepted by the lung tumor board. Given his severe pain and poor performance status, the patient received a course of palliative radiotherapy (17 Gy in 2 fractions). He reappeared in our thoracic surgeon’s office 9 months later. A repeat CXR revealed a shrunken LUL lesion compared to previous films. The patient was restaged, with no evidence of metastatic disease and negative mediastinoscopy. He eventually underwent en bloc resection of the LUL mass and chest wall. On detailed pathologic examination of the specimen, no histologically viable or clearly necrotic malignant tumor was identified in either lung or chest wall tissue. Necrotizing granulomatous inflammation highly suggestive of tuberculosis was noted in the lung, and a single weakly acid fast structure suggestive of Mycobacterium tuberculosis was identified.
Although 95% of cases are due to malignancy, a variety of other lesions can arise in the superior sulcus and cause Pancoast syndrome. We report a case where Pancoast syndrome may have resulted from the combination of lung cancer and tuberculosis, or tuberculosis alone. The pathologic specimen revealed areas of granulomatous inflammation, but also foci of fibrosis and chronic inflammation without granulomas. It is possible that these were sites of carcinoma sterilized with radiotherapy. Tuberculosis presenting as Pancoast tumor in a non-smoking man from Cameroon was recently reported. Tuberculosis and Pancoast tumor presenting synchronously has also been reported. In our case, however, the BAL was negative for AFB. In retrospect, histologic diagnosis of malignancy should have been more aggressively pursued. But in addition to suggestive cytology, several features suggested the diagnosis of lung cancer, including the patient’s smoking history and the presence of clubbing, rarely seen in TB. The apparent response of the lesion to radiotherapy is surprising. Some authors have suggested an association between radiotherapy and reactivation of tuberculosis. We found older references of radiotherapy being used therapeutically for pulmonary TB. Postoperatively, the patient completed a course of antituberculous therapy.
We report a case of Pancoast syndrome which may have represented tuberculosis in isolation, or tuberculosis combined with lung cancer. The patient’s symptoms and the lesion responded to initial palliative radiotherapy, given for presumed isolated lung cancer. Given the differential diagnosis, a histologic diagnosis should be obtained before proceeding with therapy in this context.
Anne Gonzalez, None.